Many gold sands contain cemented mud aggregates, some of which are larger than 100 mm in diameter. If they are not broken, they will be removed along with the waste rock in the screening process, resulting in the loss of gold. In addition, the cement can be cemented on gravel or pebbles, if not broken, it will cause gold loss in the screening process. On board a gold-mining ship, fragmentation and sieving are performed in the cylinder screen together. The cylinder screen is equipped with discontinuous spiral angle steel. During operation, the washing water pressure in the cylinder screen should not be less than 35 KPA, and in the land fixed separation plant, the washing deposit should be broken and sifted. Use Pinggui 50 or Pinggui 1-100 water Two guns, rinse diagonally over and over again. Water gun outlet pressure is not less than 20 KPA. Screening operation can exclude 20% of waste rock (gravel, pebble), which is indispensable for placer gold processing. The determination of reasonable screening parameters must be based on the determination data of the particle size composition of gold in the original ore sand. At present, the selection of sieve holes in placer gold mines in our country is generally 10 ~ 20 mm, if the fixed chute is used as a roughing equipment, the sieve hole can be larger, but can not exceed 60 mm. Fixed separation plant screening equipment is mostly grid screen, vibrating screen, gold mining ship with cylinder screen. Sieve up flushing can not only improve the screening efficiency, but also further break up the slime. The sieving operation of gold sands is mostly water sieve. The water sieve flushing capacity should be determined according to the washing requirements and should meet the concentration requirement of the next separation operation as far as possible. If the sluice is rough, the scouring capacity should be 814 times of the sand volume (volume ratio).
Materials less than 0.1 mm in demineralized gold generally contain little or no gold. For example, only 0.15 mm of gold is less than 0.1 mm in placer gold deposits in Hunchun gold mine, 0.18 mm gold is less than 0.1 mm gold in Huainan gold mine, and 13.77% of original ore is in the same grain grade mud. Gold less than 0.1 mm, commonly known as floating gold, is difficult to recover in the separation process, while the same size of slime interferes with the separation process, especially the mechanical separation process. Therefore, in the sanding machine concentrator, always managed to remove less than 0.1 mm of mud. Common desliming equipment in production For various specifications of desliming hopper. However, the material size is wide and the handling capacity is large, so the chute is not deslimed before separation.
Separation practice has proved that gravity separation is the most effective and economical method to treat gold sands. Because the granularity composition of gold in gold is different and the effective grain size limits of various gravimetric separation equipments are different, the reasonable separation process of gold ore should be combined operation of several kinds of gravimetric separation equipment. The gold concentrate obtained from the coarse separation section has a gold grade of 100 g / t and a heavy sand mineral of more than 1 ~ 2 kg / ton. There are three methods for the treatment of gold-bearing coarse concentrate at present: (1) the heavy sand is discarded after the gold pellets have been manually panned out by gold panning; (2) amalgamation with mercury mixing tube and heavy sand abandonment after mercury paste is obtained; (3) washing or mixing mercury by artificial method After gold is extracted, the heavy sand is sent to the cleaning plant for treatment, and all kinds of heavy sand minerals are recovered by magnetic separation and electric separation respectively. Gold recovery of gold ore: two chute separation is 70M74, chute cleaning, jig cleaning, shaker cleaning process is 75 / 80.
Statement: the reprint of the above contents by the Central South Mineral processing Network does not confirm its description. It is only for investors' reference and does not constitute an investment recommendation. Investors operate on this basis, at their own risk.
